Gripper shuttle having a thread clamp



E. PFARRWALLER GRIPPER SHUTTLE HAVING A THREAD CLAMP Aug. 21, 1956 2 Sheets-Sheet 1 Filed March 51, 1954 INVEN TOR. EEW/N PFAEEWALLER BY A TORA/EK 1956 E. PFARRWALLER GRIPPER SHUTTLE HAVING A THREAD CLAMP 2 Sheets-Sheefi 2 Filed March 31, 1954 INVENTOR. EEW/IV P-ARRWALLEE.

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A77 K/YEK GRIPPER SHUTTLE HAVING A THREAD CLAMP Erwin Pfarrwaller, Winterthur, Switzerland, assignor to Sulzer Freres, Societe Anonyme, Winterthur, Switzerland, a corporation of Switzerland Application March 31, 1954, Serial No. 420,178

Claims priority, application Switzerland April 10, 1953 15 Claims. (Cl. 139125) The invention relates to a gripper shuttle having a thread clamp which is actuated by elements effecting opening of the clamp for seizing and/or releasing a weft thread.

It is an object of the invention to provide a gripper shuttle for looms, the shuttle being equipped with a thread clamp having a first portion cooperating with an actuating element for operating the clamp to seize or grip a weft thread and having a second portion spaced from the first portion, the second portion being affected by an actuating element for operating the clamp to release the weft thread. The first portion is preferably farther away from the clamping point of the clamp than the second portion. 7

The novel features which are considered characteristic of the invention are set forth with particularity in the appended claims. The invention itself however and additional objects and advantages thereof will best be understood from the following description of an embodiment thereof when read in connection with the accompanying drawing in which 7 Fig. 1 is a view of a loom as seen from the cloth'beam side;

Fig. 2 is a part sectional side view of a gripper shuttle according to the invention;

Fig. 3 is a longitudinal section of the portion of the gripper shuttle next to the clamping point of the thread clamp which is opened by a clamp opener;

Fig. 4 is a longitudinal section of the portion of the gripper shuttle on which the clamp opener acts for releasing the weft thread;

Fig. 5 is a side view of the clamp opener for actuating the thread clamp for gripping a weft thread;

Fig. 6 is a top View of a part of the clamp opener shown in Fig. 5;

Fig. 7 is a side view of the clamp opener for actuating the thread clamp for releasing a weft thread;

Fig. 8 is a front view of the clamp opener shown in Fig.7.

The same numerals designate the same parts in all figures.

Referring more particularly to Fig. 1 of the drawing, the drive of the loom includes a motor 11 which is mounted on a right side shield 12 and which drives a belt pulley 14 by means of a belt 13. A disc clutch mounted in the pulley 14 and not shown drives the main shaft 15 of the loom. The shaft 15 primarily drives the parts of the loom which must be moved permanently or intermittently during normal operation of the loom. The shaft 15 actuates the warp beam 16 and the warp 17 which moves through the heddles supported by one or a plurality of frames 18, the latter being actuated by the shaft 15 for opening, closing, and changing of the shed. The shaft 15 also actuates the warp actuating beam 19 and the cloth beam 20 for winding the cloth 21.

A picking mechanism 22 and a shuttle receiving mechanism 23 are also driven by the shaft 15 by means of intermediate drives. A weft thread 25 is transferred to nited States Patent 0 Q a shuttle 24 in the picking mechanism 22. The weft thread is pulled from a spool 27 supported by a carrier 26 outside of the shuttle 24 and is picked by the shuttle 24 through the shed towards the receiving mechanism 23, whereupon the weft thread 25 is beaten up by means of a lay actuated by the shaft 15.

The shuttle 24, after the weft thread 25 has been disengaged therefrom, is moved onto a return mechanism 28 by suitable means in the receiving mechanism 23. The return mechanism, driven by the main shaft 15, returns the idle shuttle 24 below the shed from the receiving mechanism to the picking mechanism.

A drive 31 for a fabric control beam 19 is mounted on a left side shield 29 which is connected with the right side shield 12 by means of a box girder 30 to form a rigid frame for the weaving machine. The angular position of the beam 19 relatively to the zero position of the main shaft 15 can forwardly and backwardly be changed by means of a hand wheel 32 driving a suitable control mechanism.

Control levers 33 and control shaft 34 afford actuation of the above mentioned clutch by means of a iinkage 35 and of a brake disk by means of a linkage 36 for starting and stopping the loom from both sides of the loom. The brake, which is in a housing 37 and mounted on the main shaft 15, is applied at improper operating conditions after disengagement of the disc clutch in the belt pulley 14 for immediately stopping the main shaft 15 and all parts driven thereby. The brake in the housing 37 is disengaged in known manner by means of a control lever 33 without engaging the clutch in the disc 14. Thereupon the disconnected main shaft 15 can be turned by means of a handwheel 38 so that the loom parts driven thereby assume a desired position for restarting the loorn.

The gripper shuttle 24 (Fig. 2) comprises a hollow shuttle body 40 whose front end is closed and forms a pointed head 41. A thread clamp 42 is placed in a cavity 43 having a rectangular cross-sectional configuration, the clamp being connected by means of rivets 44 with the body 40. The rear ends of the opposed longitudinal sides of the body 40 are provided with a cut 45 and, spaced from the cut, with a circular opening 46.

The thread clamp 42 has two resilient legs 47 and 48. It is made of spring steel and so constructed that the lips 49 and 51 of the left end of the clamp 42 are pressed together due to pretension of the spring steel and form a clamp for the weft thread 25. Ridges 52 provided on the inside of the legs 47 and 48 adjacent to the opening 46 are adapted to slidably engage the element for opening the clamp for receiving a weft thread in the picking mechanism. Ridges 53 are provided on the inside of the legs 47 and 48 within the cut 45, the ridges 53 cooperating with the opener element for releasing the weft thread 25 in the shuttle receiving mechanism 23.

Fig. 3 illustrates the opener element 54 in operating position, in which a thorn 55 has pressed the legs 47, 48 so far apart that the clamp 49, 51 is sufficiently opened for unhindered introduction of the weft thread 25 which is held by a thread clamp 56 of a weft thread feeder 57. Depending on the manner of moving the shuttle 24 to the thread feeder, space for the passage of a stem 58 of the feeder between the jaws 49, 51 must be provided. The clearance a between the clamp jaws 49 and 51 (Fig. 3) is greater than the clearance b (Fig. 4) between the jaws 49 and 51 which clearance must be only sufficiently great to release the weft thread 25 so that the latter can easily be withdrawn. For the latter purpose, the thread clamp 42 is opened by means of a thorn 61 of an opener 59.

The operation of the openers 54 and 59 is known per se and described, for example, in Patent No. 2,163,760. If the shuttle 24 is moved from the shuttle return mecha 3 anism 28 by a shuttle lifter in the picking mechanism 22 (Fig. 1) to the picking position, and if the lifter revolves on an axis, the opener 54 is preferably revolvably supported on the same axis, the thorn 55 being bent to form an are which is coaxial of the rotation axis of the opener, as is shown in Fig. 5.

The thorn 54 is tapered transversely to the thread clamp 42, a wedge surface 6'2. serving for spreading the clamp legs 47, 43. The shuttle 24 is centered in its longitudinal direction by making the thickness of the thorn 55 from section 63 to the left in Figs. 5 and 6 equal to the diameter of the opening 46. Thereby an inaccurate position of the shuttle 24 in the shuttle lifter can be corrected in the shuttle lifter or, at the latest, in the thread transfer position of the shuttle whereby an interruption of service and the danger of breaking the thread clamp 42 is avoided, when the stem 58 of the Weft thread feeder 57 passes between the opened clamp jaws 49, 51.

The thorn 61, Figs. 7 and 8, is provided only on one side With an inclined surface 64- in order to place the shuttle 24 in correct position for pushing it out of the shuttle receiving mechanism 23 because only the end surface 65 of the cut %5 can produce correction of the position of the shuttle in the longitudinal direction.

The inner surfaces of the ridges 52, 53 of the two operating stations of the legs 47, 48 are situated in the same planes. These planes are parallel when the clamp 49, 51 is closed. This has the advantage that both ridges can be made in one operation.

A recess 66 is provided on the legs 47, 48 between the ridges 52 and 53 so that the longitudinal extensions 0 and d of the ridges 52 and 53, respectively, are equal to or shorter than the width of the surfaces of the thorns 55 and 61, respectively, cooperating with the ridges. This has the advantage that the entire length of the ridges 52 and 53 .is worn evenly and no edge can be produced on the legs 47, 48. Such an edge may cause rupture and breaking of a leg of the clamp 42.

if two separate operating stations are provided for the openings 54 and 59, instead of one, 52, 53 is reduced by at least one half. This produces the important advantage that the clearances a and b between the lips of the opened clamp 49, 51 will retain the required minimum measure for a long time, doubling the life of the thread clamp 42. It is of particular importance that the clearance at is not considerably changed to secure undisturbed introduction of the weft thread 25 without excessive spreading and corresponding stressing of the legs 47, 48 when the clamp 42 is new.

Because the length of the ridges 52, 53 is not greater than the engaging surfaces of the thorns 55, 61, respectively, the cross-sectional configuration of the thorns 55, 61 need not be over-accurate.

At least the inner surfaces of the ridges 52, 53 may be shot-peened in order to obtain a greater density of the surfaces and an additional reduction of wear. This may also be done with the surfaces of the thorns 55, 61. Manufacture may be facilitated, if not only the operating stations but the entire legs 47, 48 or the entire thread clamp 42 are short-peened.

In the illustrated embodiment of the invention, the thorn 55 has a greater dimension across the opening faces than the thorn 61 for reducing wear.

it lies within the scope of the invention that the ridges 53 may be opened by an opening element for receiving the Weft thread inserted within the opening 45 in the picking mechanism 22. An opening element for releasing the weft thread the shuttle receiving mechanism '23 may then be inserted in the opening 46 near the ridges 52. This arrangement will be advantageous when the pre-tension or resilience of legs 47 and 48 of the thread clamp 42 is considerable.

I claim:

1. A gripper shuttle comprising a thread clamp adapted to be opened by means of opening elements for gripping Wear of the ridges and releasing a weft thread, said thread clamp having a first operating station for an opening element for gripping a weft thread and having a second operating station for an opening element for releasing the weft thread, said operating stations being spaced from one another.

2. A gripper shuttle as defined in claim 1, the first operating station being farther away from the clamping point of said thread clamp than said second operating station.

3. A gripper shuttle as defined in claim 1, said thread clamp having two legs, each leg having an operating ridge at each operating station.

4. A gripper shuttle according to claim 3, the ridges at one operating station being spaced from the ridges of the other operating station.

5. A gripper shuttle according to claim 4, said ridges having operating surfaces, the operating surfaces of the ridges of each leg being in the same plane.

6. A gripper shuttle comprising a hollow shuttle body, and a thread clamp disposed in said shuttle body and adapted to be opened by means of opening elements for gripping and releasing a weft thread, said thread clamp having a first operating station for an opening element for gripping a weft thread and having a second operating station spaced from the first station for releasing the weft thread, said shuttle body having individual spaced openings adjacent to said operating stations for individually affording passage of the opening elements through said shuttle body to said operating stations.

7. A gripper shuttle as defined in claim 6, the opening which is nearest to the clamping point of said thread clamp being formed as a slot extending from one end of said shuttle body longitudinally of said body.

8. A gripper shuttle and two actuating elements therefor comprising a hollow shuttle body, a thread clamp in said body adapted to be opened by means of the actuating elements for gripping and releasing a weft thread, said clamp having a first operating station for one of the actuating elements for gripping a weft thread and having a second operating station for the other of the actuating elements for releasing the weft thread, said operating stations being spaced from each other, said thread clamp having two legs, each leg having an operating ridge at each operating station, the ridges of different legs pairwise facing each other, each actuating element having a thorn adapted to be inserted between one pair of said ridges.

9. A gripper shuttle and two actuating elements there for as defined in claim 8, the extension of said ridges in the longitudinal direction of the shuttle being not greater than the width of the surface of said thorns inserted between said ridges.

10. A gripper shuttle and two actuating elements therefor as defined in claim 8, the thorn of the actuating element for the operating station for releasing the weft thread being tapered transversely to the longitudinal extension of the shuttle.

11. A gripper shuttle and two actuating elements therefor as defined in claim 8, said body having an opening adjacent to the operating station for gripping a weft thread, said opening having an operating surface transversely to the longitudinal extension of the shuttle, and the thorn of the actuating element for the aforesaid operating station having a surface cooperating with said operating surface.

12. A gripper shuttle and two actuating elements therefor as defined in-clairn 8, said thorns having shot-peened operating surfaces.

13. A gripper shuttle comprising a thread clamp adapted to be opened by means of opening elements for gripping and releasing a weft thread, said thread clamp having a first operating station for an opening element for gripping a weft thread and having a second operating station for an opening element for releasing the weft thread, said operating stations being spaced from one another, and

said thread clamp having two legs, each leg having an operating ridge at each operating station, each of said 15. A gripper shuttle and opening elements as defined operating ridges having a shot-peened operating surface. in claim 14, wherein one of said opening elements is 14. A gripper shuttle comprising a thread clamp adaptthicker than the other opening element.

ed to be opened by means of a pair of opening elements for gripping and releasing a Weft thread, said thread clamp 5 References Cited in the l Of is Pat nt having two legs, and each leg being provided with opposed UNITED STATES PATENTS operating areas near the clamp aws, one of said opening 2,163,760 Moessinger June 27, 1939 elements engaging said areas at a greater distance from the clamp jaws than the other opening element. 

